Loosing the knob you can quick release the rack;

You are able to adjust the rack to horizontal and fix the position with 2 pins.

Holds 1 wakeboard and 1 kneeboard;

2 1/2" clamp comes along with rubber collars 2 3/8", 2 1/4", 2", 1 7/8", 1 3/4";

Anodized finish easy to clean and last long time.